What does the ATRIA bleeding score measure?

It estimates the annual probability of a major bleeding event (requiring transfusion, causing significant disability, or fatal) in patients with atrial fibrillation taking warfarin anticoagulation therapy.

How is anemia defined in the ATRIA score?

Anemia is defined as hemoglobin < 13 g/dL in men or < 12 g/dL in women, or a hematocrit < 40% in men or < 36% in women at the time of scoring.

How is renal disease defined in the ATRIA score?

Renal disease is defined as an estimated GFR < 45 mL/min/1.73 m² or end-stage renal disease requiring dialysis.

What bleeding rates correspond to each risk category?

Low risk (score 0-3): approximately 0.8% annual bleeding rate. Intermediate (score 4): approximately 2.6%. High risk (score 5-10): approximately 5.8% annual major bleeding rate.

Should I use ATRIA score alone to decide on anticoagulation?

No. The ATRIA score is a decision-support tool only. Bleeding risk must always be weighed against stroke risk using validated tools such as CHA2DS2-VASc. Clinical judgment and patient preferences are essential.

Does this calculator apply to direct oral anticoagulants (DOACs)?

The ATRIA score was validated specifically for warfarin. Its applicability to DOACs has not been formally validated, though clinicians sometimes use it as a general bleeding risk reference.

ATRIA Bleeding Score

Name: ATRIA Bleeding Score
Availability: InStock
Author: Nham Vu

Calculate the ATRIA bleeding risk score to estimate major bleeding risk in atrial fibrillation patients on warfarin.

Patient Risk Factors

Select all that apply to the patient.

Anemia Hgb <13 g/dL (men) or <12 g/dL (women) +3 pts

Severe Renal Disease eGFR <45 mL/min/1.73 m² or dialysis +3 pts

Age ≥ 75 years Patient is 75 years old or older +2 pts

Prior Bleeding History of any hemorrhagic event requiring attention +1 pt

Hypertension Diagnosed hypertension or on antihypertensive therapy +1 pt

Select risk factors and click Calculate Score

Summary